Origin

Masaki Sumitani is part of the Japanese comedy duo known as Razor Ramon, a name which he also used in his brief wrestling career. Sumitani and his friend Makoto Izubuchi formed Razor Ramon in 1997. Sumitani's most well-known performing character is Hard Gay (ハードゲイ, Hādo Gei), also called "HG", Razor Ramon Hard Gay or Razor Ramon Sumitani, an eccentric supposedly gay man wearing tight black leather and PVC clothes and acting with overacted gay mannerisms.

According to Wikipedia, Sumitani had been a popular stage comedian, performing a few different characters for a few years befor joining Yoshimoto Kogyo Co., Ltd. In 1999.

Excerpt from Wikipedia on Yoshimoto Kogyo:

Yoshimoto Kogyo Co., Ltd. (吉本興業株式会社, Yoshimoto Kōgyō Kabushiki-gaisha?) (TYO: 9665) is a major Japanese entertainment conglomerate, with its headquarters based in Osaka. It was founded in 1912 as a traditional theatre, and has since grown to be one of the most influential companies in Japan, employing most of Japan's popular owarai (comedy) talent, producing and promoting the shows they appear in, and even maintaining its own amusement park.

Sumitani introduced the Hard Gay character (known in Japan as Hādo Gei) in 2002, growing to national renown by 2005 when Hard Gay became a weekly feature on the Bakushō Mondai no Bakuten!(Daibakuten) variety show. The character represents a common stereotype of American gay subculture to the Japanese audience and does not represent any Japanese gay subculture. Because of this, it was allowed to be aired and not deemed offensive to Japanese audiences.
On the show, Hard Gay goes around performing acts of charity (or yonaoshi, “social improvement” → source: wikipedia link) for unsuspecting bystanders, wearing his fetish outfit while accompagnied by the Ricky Martin's "Livin’ la Vida Loca" song.
He has also trademarked gesture and vocalizations such as his "pelvic thrust", his "Hoooooo" (フゥ～!) or "Foohhhh!" (フォー！) running jokes shouts or also his "Sei sei sei sei sei" shout with his palm in front of the person’s face.

The main theme of Hard Gay's act relies on the idea that Hard Gay is a foreigner, and as such, can get away with outlandish behavior. The setting of each video

Spread

The first Hard Gay video to be uploaded to Youtube was a video of a live performance, uploaded by user SaffronsGhost on January 19th, 2006. After three years, the video has just under 70,000 views.

On February 19th, 2006, a user by the name of Grommet on the forums at Bakakage.net started a thread entitled For the NANA fans (link via Wayback Machine) and posted a link to another Hard Gay video. Unfortunately, this video has been removed due to copyright violation.

On February 22nd, 2006, another Hard Gay thread was created. The thread was called In Bridget we trust (link via Wayback Machine) and contained an image of Hard Gay hotlinked from 420chan.

Http://www.hard-gay.org, was first registered on August 27th, 2006 and archived by archive.org on November 7th, 2006. The site was available in English and Japanese right from the start.
This WMV episode with subtitles was made easily accessible to English-speaking audiences at least as early as November 7th, 2006.

It appears that the first Wikipedia article to be published on Hard Gay was on October 11th, 2005.

The Japan Times printed a story on Hard Gay in English on July 17th, 2005.

Hard Gay videos

His offbeat humor clashing with the japanese more conservative code of political politeness led to worldwide fame when videos from the show were uploaded on Youtube, and subbed in english:

Here, he went to Yahoo Japan company:

Social improvement:

He even went to Tomy's director's house to have his own Pop-up Pirate version:

The original [Bakafish] videos have been deleted due to copyright infrightement, sadly. They had many more views than the new ones.
You can find here (link via Wayback Machine) the forum community that helped translating and subbing HG's videos.

Hard gay also made a japanese version of "Young Men", from YMCA:

And a song of his own (warning, NSFW):

He was featured on "Lost in Tokyo", a Dutch and Flemish game show and has also appeared in multiple episodes of Jonathan Ross' Japanorama on the BBC.
Finally, he made cameo appearances in Gantz and The Melancholy of Haruhi Suzumiya animes/mangas as well as several Japanese other shows and games.

Hard Gay cameo appearance in the Nintendo game: Tingle RPG:

British Hard Gay fans parodied their idol:

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